Solution (a)

Explanation

• Statements 1, 3 and 4 are correct. IRENA was established in 2009 as an intergovernmental organisation dedicated exclusively to promoting renewable energy worldwide. India is a founding member, and the organisation works closely with the UN system, particularly towards SDG-7 (Affordable and Clean Energy). It publishes flagship reports such as the Renewable Power Generation Costs Report, Renewable Energy Capacity Statistics, and the World Energy Transitions Outlook.
• Statement 2 is incorrect because IRENA is headquartered in Abu Dhabi, United Arab Emirates, whereas Vienna hosts organisations like the IAEA and UNIDO.

UPSC often creates confusion by interchanging headquarters of international organisations, making location-based elimination an important strategy.

Why this question?
Tests headquarters confusion among international energy organisations.

Why important for UPSC?
Climate governance and renewable energy institutions are recurring Prelims themes.

PYQ Pattern Link
Similar to UPSC questions comparing IEA, ISA, IRENA and IAEA.

Solution (a)

Explanation

• Statements 1, 2 and 4 are correct. Vikram-I, developed by Skyroot Aerospace, is India’s first privately developed orbital-class launch vehicle, representing a milestone in India’s commercial space ecosystem. It is specifically designed for launching multiple small satellites with rapid launch readiness.
• Statement 3 is incorrect because only the first three stages use solid propulsion, while the fourth stage is powered by a hypergolic liquid propulsion system using MMH and NTO through four Raman engines.

UPSC frequently frames questions by replacing mixed propulsion with a single propulsion type, making careful reading essential. Aspirants should also distinguish Vikram-S (suborbital) from Vikram-I (orbital-class).

Why this question?
Tests distinction between propulsion stages and private launch vehicles.

Why important for UPSC?
Private space sector reforms remain a high-priority science topic.

PYQ Pattern Link
Comparable to UPSC questions on PSLV, SSLV, GSLV and Chandrayaan missions.

Solution (b)

Explanation

Option (b) is correct. The Santhal Hul, which began on 30 June 1855 at Bhognadih in present-day Jharkhand, was led by Sidho Murmu, Kanho Murmu, Chand Murmu, Bhairav Murmu, Phulo Murmu and Jhano Murmu. It was directed against the exploitative policies of the British East India Company, oppressive zamindars, mahajans and colonial land revenue practices in the Damin-i-Koh region. Option (a) describes the Munda Ulgulan (1899–1900) under Birsa Munda. Option (c) refers to the Rampa Rebellion (1922–24) led by Alluri Sitarama Raju. Option (d) incorrectly links the revolt with the Doctrine of Lapse, which was unrelated to the Santhal uprising.

Why this question?
Differentiates major tribal revolts through chronology and leadership.

Why important for UPSC?
Tribal resistance movements are repeatedly tested in Modern History.

PYQ Pattern Link
Similar to UPSC questions comparing Santhal, Kol, Bhil and Munda uprisings.

Solution (a)

Explanation

• Statements 1, 2 and 4 are correct. Marburg Virus Disease is caused by viruses belonging to the Filoviridae family, the same family that includes the Ebola virus. Its principal natural reservoir is the Egyptian fruit bat (Rousettus aegyptiacus). Infection initially occurs through prolonged exposure to bat-inhabited caves or mines, while subsequent human transmission occurs through direct contact with infected blood, body fluids or contaminated materials.
• Statement 3 is incorrect because Marburg virus is not an airborne disease. At present, no WHO-approved vaccine or specific antiviral treatment exists, and management remains primarily supportive.

UPSC often differentiates zoonotic diseases based on reservoir host and transmission mode.

Why this question?
Tests transmission mode rather than simple disease identification.

Why important for UPSC?
Emerging zoonotic diseases remain an important science-health topic.

PYQ Pattern Link
Comparable to UPSC questions on Ebola, Nipah and CCHF.

Solution (a)

Explanation

• Statements 1, 2 and 4 are correct. INS Trikand is a Talwar-class (Project 11356) stealth guided-missile frigate serving with the Western Fleet of the Indian Navy. It was constructed at the Yantar Shipyard in Kaliningrad, Russia, and commissioned on 29 June 2013. Designed as a multi-role warship, it can undertake anti-surface, anti-submarine and anti-air warfare. Its major weapon systems include BrahMos supersonic cruise missiles, the Shtil surface-to-air missile system, torpedoes and anti-submarine rockets.
• Statement 3 is incorrect because INS Trikand uses a Combined Gas and Gas (COGAG) propulsion system, not Combined Diesel and Diesel (CODAD). UPSC often creates elimination traps by interchanging propulsion systems across different classes of naval vessels.

Why this question?
Tests conceptual distinction between naval propulsion systems and warship capabilities.

Why important for UPSC?
Indian Navy platforms and maritime security are recurring defence themes.

PYQ Pattern Link
Similar to UPSC questions distinguishing destroyers, frigates, submarines and aircraft carriers based on propulsion, class and operational role.